Police are on the lookout after the Seoul city government received two emails threatening that hundreds of bombs have been planted at City Hall and other locations around the country.

The Seoul Metropolitan Police Agency said on Wednesday that the emergency 112 call from the city came at around 9:10 a.m.

Aside from Seoul City Hall, locations being searched include the Supreme Prosecutors' Office, the city halls of Busan, Daegu, Suwon and Hwaseong in Gyeonggi Province, as well as Seoul National University, Yonsei University and Korea University.

The writer of the emails claimed that 270 million bombs had been installed and that they plan to set them off on Wednesday and on Thursday, although the ongoing search has so far found no items of suspicion.

The latest threats were sent under the name of the same law firm in Japan that was used in earlier threats of terrorism against main opposition Democratic Party(DP) leader Lee Jae-myung, Seoul's Namsan Tower, and the National Museum of Korea.

The police suspect all the threats were sent by the same person or group with a Japanese internet protocol address and have requested cooperation from the country’s authorities.